What's the difference?

[ABCwarrior]

I've been looking on the web at consumer units. I'm totally baffled now I must admit- I need a CU mainly for a shower, but does this need to have an RCD or RCBO(30ma breaker) AND the relative 40A MCB for the shower? Or would an old fashioned 63A DP switched unit plus the 40A MCB do? Is this method now out of date/illegal or something? The CU will probably be only for the shower, maybe an extra slot(2 way?) for the possible running of a cable for power(16A) to a shed/workshop in the future....

 

[ABCwarrior]

Or are these DP switched units designed to have RCBO's in them?!

 

[ricicle]

You need overload protection and additional 30mA protection. An RCBO will do both. Seperately an MCB/fuse and RCD will be needed.

 

[RF Lighting]

But you also need DP isolation.

A CU with a main switch and an RCBO would be best if you are looking to run a shed off this CU in the future.

If you get a metal clad CU then you could gland a SWA directly in to it (assuming you don't have a TT supply)

 

[ABCwarrior]

So a CU with a main switch coupled with RCBO's, or a CU with an RCD type mainswitch coupled with MCB's, but most definitely NOT a standard mainswitch with only MCB's?

 

[ABCwarrior]

Cheers RF....after googling those terms got a rough idea about armoured cable and earth types....

Might stick to a dedicated shower CU for the time being, after all there's be more room at the Henley block things for adding a dedicated shed CU later?